Back in the days when Bankside Power Station actually burned oil, it stored its fuel supply in a trio of enormous round tanks lying beneath the rear of the building. Nobody can afford such a quantity of oil these days, but the tanks are still down there, and Tate Modern has big plans for them. Last weekend, small groups of museum members toured the eerie underbelly of the institution for a look at things......

View Larger Map Cold War bunkers, abandoned Tube stations, buried rivers, deep level shelters...London's concealed features are among its most intriguing. So, in age-old Londonist tradition, we've created a map to try and show what a hollow city this is. And we need your help. We've plotted the more obvious features - the Fleet River, Zone 1 ghost stations, the Kingsway telephone exchange, etc. But we know there's a lot more down there. Please use......

Crossrail, the Channel Tunnel rail link, basement developments – underground London is growing as fast as the surface city. The past, present and future of our subterranean spaces are celebrated in the latest exhibition at New London Architecture. To be honest, you can enjoy most of the show from the comfort of your laptop by downloading the guide. However, if you're in the Tottenham Court Road area, it's worth popping in to see the......